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Stock# 99887
Description

Extensive Archive of Documents and Letters of Medal of Honor Recipient

Freedman's Bureau, Western Frontier Indian Campaign

Remarkable and substantial archive documenting the military career of an important American Army officer, Medal of Honor recepient Joseph A. Sladen. Covers Salden's distinguished Civil War service as well as his frontier Indian campaign experiences. Includes personal manuscript journals, an amazing bound collection of General Orders, the latter mostly printed at frontier western posts, including Washington Territory, Utah Territory, Wyoming Territory, Texas, and the like. Also includes a large collection of Sladen's correspondence, mostly personal family letters. There are also numerous rare ephemeral company rosters and death notices of soliders laid into the bound volumes of General Orders. 

Sladen's diaries and journals make interesting reading and stand as prime historical source material for the military campaigns and posts to which he was attached. He includes good descriptions of the places he visited, opening a window to understanding his role, through the military, in pivotal moments in U.S. history.  For instance, a long entry from June 18-22, 1883, describes Yellowstone, including descriptions of the terrain and geysers.

This multi-faceted archive, combining official documents with intimate family correspondence, represents a significant untapped research opportunity. Covering most of Sladen's military career, it encompasses the final years of the Civil War, the Freedman's Bureau, and frontier western military campaigns against Native American tribes.  

Sladen's close association with General Oliver Otis Howard, for whom he served as aide-de-camp, is an important thread through most of Sladen's impressive Army career. Gen. Howard, a fellow Medal of Honor recepient styled by many as "the Christian General" due to his deep evangelical religious beliefs, was put in charge of the Freedman's Bureau in 1865. The Bureau had as its mission the integrating of former enslaved persons into Southern society and politics. Howard is remembered today as the namesake of Howard University.

As an officer bringing his Civil War experience to bear in the West, Sladen faced a new kind of conflict against Native American tribes, with his journals and papers highlighting the challenges of military engagement on the frontier​. In the broader context of the Indian Wars, Sladen's personal archive of documents and letters reflects the complex and often tragic interactions between the U.S. military and Native American tribes.

Joseph A. Sladen

A distinguished Army officer who began his military career during the Civil War with the 33rd Massachusetts Infantry, Joseph A. Sladen was awarded the Medal of Honor for distinguished gallantry in the Battle of Resaca, Georgia (May 14, 1864).

Joseph Alton Sladen, born in England in 1841, moved to Massachusetts at a young age. He enlisted in the Union Army during the American Civil War, serving in the 33rd Massachusetts Infantry Regiment. He was awarded the Medal of Honor, with a citation for bravery at the Battle of Resaca in 1864, where he voluntarily joined the fight and inspired his comrades. He participated in the Atlanta and Alabama campaigns. Aide-de-camp to General Howard, engaged in Sherman's March to the Sea. After the war, Sladen continued his service in the army, transitioning into the post-war era with assignments such as aide-de-camp to General Oliver Otis Howard (who had lost his right arm at the Battle of Fair Oaks in 1862) and serving in the Freedmen's Bureau, the organization charged with supervising nearly 4 million liberated enslaved people.

Sladen's most notable contribution during the Frontier Indian Wars was his involvement in the 1872 peace negotiations with the Chiricahua Apache leader Cochise. As General Howard's aide-de-camp, Sladen journeyed through New Mexico and Arizona, a pivotal expedition he detailed in his account "Making Peace With Cochise." This successful mission led to a treaty with Cochise, marking a significant achievement in the fraught relationships between Native Americans and the United States government during this era.

In later years Sladen faced personal challenges, including severe injuries leading to the loss of his leg, but he continued his military career, participating in the Nez Perce War of 1877 and the Bannock War of 1878. His dedication to the army saw him serve in various military capacities, including time at the United States Military Academy and eventually reaching the rank of captain before retiring due to his disability in 1889.

Post-military, Sladen settled in Portland, Oregon, embarking on a successful career in insurance and banking, and serving as a clerk of the U.S. Circuit Court. He remained active in civic and professional organizations, contributing significantly to his community until his death in 1911. His remains were reinterred at West Point Cemetery in 1929.

The present collection consists of the following items:

  • 1877 pocket diary journal. Diced sheep leather binding. 5 x 3 inches. Sladen's ownership name on front cover and inscribed on front flyleaf: "J. A. Sladen, 14th Infantry, Portland, Oregon. Jan. 1, 1876 [sic]. Filled with brief manuscript entries.
  • 1878 manuscript journal volume, spine title "Records." Sporadic entries, 1878-1883. Small octavo. 19th-century sheep ledger-style binding, with gilt-ruled red dyed-sheep onlays on covers. 8 1/2 x 6 inches. Marbled endpapers. Ownership signature on front flyleaf: "J. A. Sladen, U.S. Army." 212 pages filled with manuscript text. Numerous tipped-in printed and pictorial ephemeral items.
    • Opening entry dated at Fort Vancouver, W.T., Dec. 19, 1878: "After several futile attempts at a diary I give it up and now commence a journal that I may, when the Divine [?] shall move, jot down my thoughts or deeds to help my feeble 37 year-old memory. Day before yesterday the General (Howard) received a dispatch from the Dalles, from a Mr. D. P. Ballard to the effect that he had been sent as a messenger from a public meeting at Yakima to come to the Dept. Commander and ask for help for a party of 15 Indian police and 35 citizens as a Sheriff's posse which had gone to Priest Rapids to arrest the murders of Perkins and wife. These murderers are Indians and are supposed to be in Moses' band."
    • This journal also includes several entries made "at sea" during voyages in the Pacific and Atlantic, accomapanying Gen. Howard.
    • Entry dated Sept. 20, 1881: "President Garfield died last night. The whole nation is in deep affliction for him. He was shot on July 2, and has fluctuated between life and death ever since. No sorrow has been so universal in this nation as this. The sympathy has been confined to no section and to no party."
    • July 14, 1882, West Point, N.Y.: "... Gen. Howard is assigned to the Command of the Dept. of the Platte relieving Gen. Crook, and that Crook goes to Arizona, and Wilcox joins his regiment and takes it to the Dept. of the Platte. Glorious news!"
    • Nov. 14, 1882: "Gen. Howard and myself left Omaha Friday on the 12:15 train west. On the train we find Gen. Morgan, Commissary, enroute to his new station, San Francisco, accompanied by his wife and little girl."
    • Nov. 15, 1882: "Lunched at Cheyenne where Capt. Lord, A.Q.M. met us. Saw Capt. Willard, Commissary, Capt. Mears of the 9th and some others. Met genial Dr. McElderry, en route to his new station, Fort Robinson, from Bridger, and had a long and pleasant talk with him over old times and old friends at Fort Klamath."
    • Nov. 18. 1882, Fort Washakie, Wyoming: "Today the General inspected the buildings and post.... This afternoon we rode to the Hot Springs, five miles distant, and took a bath... On our return we had a visit from "Sharpnose", an Arapaho, who is enlisted as a scout by Gen. Sheridan's order, though he does no scouting. His uniform, for a scout, was noticeable and consisted of an officer's blouse, with a pair of Cavalry Major's straps; a Cavalry Corporal's trousers; a soft black hat with an officer's cord, and moccains on his feet. He carefully unwrapped from a numbers of layers of dirty rags, a number of letters of commendation, among which was one from Gen. Crook and another from General Garfield, and with the latter his photograph and signature on it. The Indian Agency is 1 1/2 miles from here. The reservation is a very large one and covers a very valuable tract of country. The Indians are Shoshones and Arapahoes, numbering in all about 1800 and about equally divided. They speak different languages, and a curious feature is that no one can communicate with Arapahoes in their own language, all talk with them being by means of the sign language, at which all Arapahoes are very expert. Indeed their vocabulary is so small that a great deal of their communication with each other is by signs. One of the Indians in Moore's store explained to me, through an interpreter entirely by signs that Chief Washakie was absent on a hunt, when he went, where he is and when he would return."
    • Further entries at stops along the route: Big Sandy, Blackfoot, Ogden, Salt Lake City.
    • Nov. 24, 1882: "Reached Salt Lake City at 1 P.M. and found Capt. Penney, R.Q.M. of the 6th Infantry awaiting us. He took us downtown where we lunched, and then went with us to see Bishop Sharp, the Pres. of the Utah Central R.R. The Bishop was out but sent word to the General offering us the Director's Car tomorrow or the pay car today, to go to Milford, en route to Fort Cameron.... The General found on the train a Mr. Matthews, half brother of Schuyler Colfax's and he brought him into the car and made him a travelling companion. The ride during the aftenoon was delightful, and the scenery very beautiful. The numerous Mormon towns, and villages, the well kept farms, the beautiful mountain ranges on either side of us, and the extensive valley through which we rode nearly all afternoon, were sights long to be treasured. The General spent most of his time in the passager coach talking with the Mormons and getting hold of the Mormon question from their own side."
    • Nov. 25, 1882: "We reached Milford at daylight this morning, and found an ambulance from Fort Cameron awaiting us.... Our route lay along extensive valleys, bounded by mountain ranges and here and there we could see evidences of the extensive mining operations carried on about. At Minersville, we found a little collection of neat looking houses, a waterfall, dam, canal and gristmill. The only appoach to a Hotel was a barroom kept by a Jew, named Lessing, who appeared to be his own best customer.  A declination to drink with him, from our party, semed to surprise him very much. We changed animals here and then pushed on for Beaver.
    • April 5, 1883, Creighton, Nebraska: "General Howard and I left Omaha this morning at 8:15 for this place."
    • April 6, 1883, Fremont, Nebraska: "I loafed about the town, a brisk, lively business place, until noontime, meeting Capt. Geo. W. Quimby, who used to be one of our scouts in the Army of the Tennessee, and who afterwards became a Captain in the 128 U.S.C.T. [United States Colored Troops] - Gen. C. H. Howard's regiment. He is in the real estate business, has a nice farm, and seems to be in comfortable circumstances, and much looked up to as one of the leading men of this section.... The evening train brought Mr. Benedict, Indain Inspector, enroute to the Santee Agency. The Agent, Mr. Lightner, came in this evening from the Santee Agency, with three of his Indians, to meet General Howard.  About 8:30 this evening, the Grand Army Post with a brass band came to serenade the General, and conducted him to the Cong. Church where he addressed them for half an hour. Sat up till midnight talking to the Indians."
  • 1878 pocket diary journal. Diced sheep leather binding. 5 x 3 inches. Sladen's ownership name on front cover and inscribed on front flyleaf: "J. A. Sladen, U.S. Army, Portland, Oregon." Partially filled with brief manuscript entries.
  • 1883-1885 manuscript journal volume, including "Trip to and through the Yellowstone Park." Spine label: "Record / J. A. Sladen, U.S.A." Quarto. 19th-century sheep ledger-style binding, raised spine bands, red dyed-sheep overlays on blind-paneled covers, with gilt fillet borders. Marbled endpapers. Ownership inscription on front flyleaf: "Private Journal, J. A. Sladen, U.S. Army / May 1, 1884." First 56 pages filled with manuscript text, remaining leaves in volume are blank. Entries headed: On West Bound, U.P. Train, June 1883: "We had also as travelling companions Mr. & Mrs. Flagler of New York, the former secretary of the Standard Oil Company, the latter his bride. On West Bound train to Ogden, June 13, 1883: Just before leaving, I met at the station, Captains Lee and Pollock.... And Dr. Vickney, Asst. Surgeon and post surgeon at Ft. Russell. Dr. Vickney reminding me that we met at Fort Wingate, N.M. in 1872...; Camp Bright, Antelope Valley, Idaho, June 15, 1883: "The ride this morning was a beautiful one. To our right was the Rocky Mountain chain, broken here and there by high peaks, like the Tetons, with many prominent points in and about the Yellowstone Park..."; Omaha, Neb. May, 1885; the final entry in the volume is dated at Portland, Oregon, May 30, 1891.
  • 1892 pocket diary journal. 3 3/4 x 3 1/2 inches. Black damasked cloth, a.e.g. Binding edges and spine frayed. Inscribed on flyleaf: "Capt. J. A. Sladen / Portland, Or. Special Agent, German American Ins. Co. of N.Y." Filled with brief manuscript entries.
  • 1893 Pocket diary journal. Leather bound, a.e.g. 4 x 2 inches. Inscription on front flyleaf: "Capt. J. A. Sladen, 253 N. 22nd St., Portland, Ore." Filled with brief manuscript entries.

General Orders Journal Books, 1863-1894: Atlanta Campaign, 14th U.S. Colored Infantry; Peace Mission with Cochise, Arizona Territory, and other Western posts:

  • 3 bound volumes containing over 250 signed General Orders relating directly to Sladen's military service. Two of the volumes with special letterpress titlepages printed in Portland, Oregon (1877) and Omaha, Nebraska (1885): "Personal Orders. General and Special Orders, Relating to Joseph A. Sladen." These are remarkable volumes comprising original General Orders, most printed on makeshift army presses and by definition very rare. Most of the G.O. are single sheet letterpress-printed, but the earlier examples present here are manuscript on special printed letterhead, notably that of the Office of the Commissioner for the Organization of U.S. Colored Troops at Nashville (1864). Many are signed by O. O. Howard. The examples from Western frontier posts are particularly interesting as early examples of Western frontier printing. Such ephemeral army imprints are very rare and were issued for official communications from commanding officers to their subordinates. The earliest example here is dated May 21, 1863, which announces Sladen's rank as a corporal and assigning him as a clerk; the last is dated December 4, 1894, placing Sladen on the list of retired officers. The group covers Sladen's Civil War and western frontier service, including the Atlanta campaign with the 14th U.S. Colored Infantry, 17th Infantry, 26th Infantry, and 14th Infantry; present here is the General Order assigning Sladen to the peace mission with Cochise in Arizona Territory.
  • Notable posts represented in the G.O. collection, standout Special Orders, printed rosters and the like, listed below:
    • Bureau of Refugees & Freedman, Washington and Nashville
    • Office of the Commissioner for the Organization of U.S. Colored Troops. Nashville. 1864.
    • Headquarters Army of the Tennessee, Special Field Order [printed], Beaufort, S.C. Jan. 5, 1865: "The General Commanding wishes to remind the offivers and soldiers of this army, that all the land on this, Port Royal Island, is now owned by people loyal to our Government, and to urge the kindest treatment of them personally, and respect for their property. Maj. Gen. Howard."
    • Austin, Texas
    • Fort Laramie
    • Wyoming Territory
    • Montana Territory
    • Portland, Oregon
    • Fort Walla Walla, Washington Territory
    • Fort Colville, Washington Territory
    • Camp Douglas, Utah Territory
    • Fort Vancouver, Washington, Territory
    • Aide-de-camp to General O.O. Howard at West Point
    • Omaha, Nebraska
    • Vancouver Barracks, Washington Territory, his last assignment
    • Headquarters, Division of the Pacific, San Francisco
    • Roster of Commissioned Officers, Twenty-Sixth Infantry, n.d. Printed roster, with extensive manuscript emendations.
    • Roster of Commissioned Officers, Twenty-Sixth Infantry. Sept. 1, 1867. Austin, Texas.
    • Roster of Commissioned Officers, Twenty-Sixth Infantry, March 1, 1868. Headquarters at Brownsville, Texas.
    • Roster of Commissioned Officers, Twenty-Sixth Infantry, July 15, 1868. Headquarters at Brownsville, Texas.
    • Roster of Commissioned Officers, Twenty-Sixth Infantry, January 1, 1869. Headquarters at Brownsville, Texas. Folded sheet.
    • Headquarters, District of Texas, Austin. Jan. 7, 1868. Printed notice cocerning "drunken row" stemming from a social event celebrating the marriage of an officer of the 35th Infantry at San Antonio. Lists four officers who were charged with "unofficerlike" conduct. Austin Texas, 
    • Roster of the Commissioned Officers of the Fourteenth U.S. Infantry. Colonel Lewis C. Hunt, Brevet Brigadier-General. August 31, 1885. Vancouver Barracks, W.T.: Headquarters. Printed roster.
    • Bureau of Refugees, Freedmen, and Abandoned Lands. Special Orders No. 189. Washington, D.C. Dec. 17, 1869.  Appointing J. A. Sladen as commissioner for Washington, D.C. in special commission to hear complaints of claimants for government bounty "made against officers or agents of this Bureau or other persons concerned in the payment of bounties to colored soldiers, sailors, or marines."
    • Commissioned Officers of the 14th Regiment U.S. Infantry. May 10, 1871. Head Quarters, Fourteenth Infantry. Fort Laramie, Wyoming Territory.
    • Commissioned Officers of the 15th Regiment U.S. Infantry. June 30, 1873. Fort Laramie, Wyoming Territory. Fourteenth Infantry Press. Printed on goldenrod paper stock.
    • Printed notice announcing the death of First Lieut. Levi H. Robinson, "who was killed by Indians on the 9th inst., while on duty in charge of escort and lumber train, near Laramie Peak, W.T."  Fort Laramie, W.T. February 19, 1874. The notice extends sympathy to his wife, who had previously lost her parents in an Indian attack, with this poignant note: "To his wife--orphaned by the hands of the ruthless savages, and now doubly bereft by the death of the one she held most dear..."
      • Fort Robinson, in northwest Nebraska, was named after the Lieutenant Levi H. Robinson, who was killed by Native Americans from the Red Cloud Agency in 1874. The fort was initially set up to protect the Red Cloud Agency and provide security for the nearby Sidney-Deadwood Trail to the Black Hills and the surrounding region.The fort's strategic importance was amplified in the mid-1880s with the arrival of the Fremont, Elkhorn & Missouri Valley Railroad, facilitating rapid troop deployments to conflict zones. This enhancement, alongside the fort's expansion, positioned it as a critical military post in the region, eventually surpassing Fort Laramie in significance​​. Fort Robinson also played a significant role in African American military history. Starting in 1885, it became home to the first African American soldiers of the Ninth Cavalry, marking the beginning of a significant period where the majority of troops stationed there were African American, up until 1907​​.

    • Commissioned Officers of the Fouteenth Regiment U.S. Infantry. Camp Douglas, Utah Territory, May 15, 1875.

Original correspondence Between J. A. Sladen and his son Fred W. Sladen

A large group of over 150 handwritten (and a few typed) family letters. The bulk of the correspondence is between Joseph A. Sladen and his son Frederick Winchester Sladen, mostly while the latter was a cadet at West Point, with a few letters from Mrs. Sladen to her son Fred, and others from siblings Harry and Frank, also addressed to their brother Fred while he was at West Point. Fred W. Sladen would go on to a distinguished military career of his own, reaching the rank of colonel by the time of WWI, and decorated with the Distinguished Service Cross and the Distinguished Service Medal, eventually retiring as a Major General. During World War I, the younger Sladen served as commander of the 5th Infantry Brigade, part of the Third Infantry Division.

About half of the letters are by J. A. Sladen, from a variety of military posts, including western frontier locales. Includes several typed letters from father Sladen on official United States Circuit Court stationary to Fred as West Point cadet during the elder Sladen's post-military career when he served as a U.S. Circuit Court clerk. The correspondence, comprised of densely packed text, reflects a loving father-son relationship, at times conveying stern advice, but sympathetic withal, and full of interesting family news. The elder Sladen occasionally reports on events at his various western army posts (Headquarters Department of the Platte, Omaha, etc.), referring to Gen. Howard, detailing his movements in the west, as well as noting meetings with various officers, and the like. These letters stand as a valuable example of an intimate family correspondence for the time - they cover a full gamut of topics: social life, sports, studies at West Point, news of other Sladen brothers at Yale and Stanford, horses, books, politics (including many references to members of Congress), family finances, fatherly advice about military career advancement, the Spanish American War, and the occasional surprise (e.g. a gas explosion at the Portland, Oregon post office in 1897), and much more. The correspondence truly reflects the lost art of letter writing.

Highlights and excerpts from the letters:

Nov. 29, 1885, J. A. Sladen from Vancouver Barracks, Washington Territory, includes a hand-drawn map of the military installations and grounds at Vancouver Barracks. 

March 4, 1888:  J. A. Sladen writes from Vancouver Barracks, W.T. complaining about the political climate during the administration of Grover Cleveland:

We have not a single solider in the administration, but thank Heaven, we have in the house, and I would rather a thousand times trust the army in the hands of Confederate Brigadiers than to the tender mercies of the old war time Coppperheads and "peace-at-all-hazards" Democrats. I have no patience with those cowards who staid in the rear, howling at the government, and who did not have the courage to fight on one side or the other. And now these fellows are hauled out of their obscurity and given the management of men who did the fighting.

An undated (ca. 1898) letter from J. A. Sladen written on New Haven hotel stationery reports on the death of Capt. Melville Wilkinson, a controversial figure in Indian education who was superintendent of the Forest Grove Indian School in Salem, Oregon, which was associated with the Chemawa band of the Kalapuya people of the Willamette Valley.  Wilkinson, who, like the elder Sladen, served as an aide-de-camp under Gen. O. O. Howard, was killed at Leech Lake, Minnesota during the Battle of Sugar Point in Oct. 1898. This skirmish is often styled the  "the last Indian Uprising in the United States":

... Last night the news brings the sad intelligence of the killing by Indians of our old friend Captain Wilkinson and six of his company. Poor fellow, he had just gotten back from the Santiago campaign, through which he had gone without a scratch, and was sent out with his company to assit a U.S. Marshal to arrest some Indians... I hear you are booked for Manila for a long time.

A letter of Nov. 24, 1898 discusses Fred's trip with the Filipino leader Emilio Aguinaldo during the Spanish American War: "Your letter concerning your trip with Aguinaldo was most interesting, and I showed it to a number of people, who are interested in it. The Oregonian wanted to publish it, and I finally consented..."

Several letters from the 1889-88 convey the elder Sladen's opinions on the Spanish American war, along with interesting commentary on the domestic situation. On May 10, 1899, Sladen writes: "If the aggregation of wealth, and the making of trusts, and the segregation of aristocrats, keeps up much longer, the average American citizen will stand little chance either in the struggle for life or in the apportionment of public positions. I see that the war in the Phillipines still continues notwithstanding that Major Strong is disabled. It is very gratifying to me to be able to get all the particulars of his condition from the daily papers of New York.... The worst man sent back from there [Philippines] is a general from Minnesota, I think his name is Reeve; he is constantly writing to the anti-imperialists, and their papers, showing how badly we treat those innocent natives, and of how cruelly Gen. Otis is carrying on the war..." 

Regimental histories and related books from J.A. Sladen's personal library, most with his ownership signature:

  • Eighth Annual Report of the Board of Indian Commissioners for the Year 1876. Washington. 1877. 108 pages. Folding color lithographmap: "Map Showing the Nez Perce Indian Reserv[atio]ns and the Wallowa Valley." 
  • Boies, Andrew J.: Record of the Thirty-Third Massachusetts Volunteer Infantry, from Aug. 1862 to Aug. 1865. Fitchburg: Printed by the Sentinel Printing Company, 1880. 168 pages. Frontispiece portrait. Original cloth. Ownership signature of J.A. Sladen.
  • Underwood, Adin B.: The Three Years' Service of the Thirty-Third Mass. Infantry Regiment 1862-1865. And the Campaigns and Battles of Chancellorsville, Beverley's Ford, Gettysburg, Wauhatchie, Chattanooga, Atlanta, the March to the Sea and Through the Carolinas in Which It Took Part. Boston: A. Williams & Co., 1881. 299 pages -+ unpaginated section of tables.
  • 1869 Military Record of Civilian Appointments in the United States Army. By Guy V. Henry. Vol. 1. Original pictorial gilt green cloth. Sladen is listed, with a biography

Miscellaneous items:

  • [Fred W. Sladen's small disbound autograph volume]. Dated Dec. 27, 1880. 2 3/4 x 4 inches. Vancouver Bks, Washington Territory. Fred Sladen was Joseph Sladen's son.
Condition Description
Collection contains: 6 19th-century manuscript diary and journal volumes of various sizes; 3 custom-bound quarto volumes of General Orders; and over 150 original manuscript letters (many still in original mailing envelopes). Also 4 published regimental histories (see below for detailed descriptions). Condition varies from good to near fine. The manuscript items are generally clean and nice.
Joseph Alton Sladen Biography

Joseph Alton Sladen was born in Rochdale, England, on April 9, 1841. Following his father James Sladen's early death, his family relocated to Lowell, Massachusetts, where young Joseph began working in mills and factories at age nine while attending school intermittently.  

In 1862, Sladen enlisted in the Union Army, joining the Massachusetts 33rd Infantry. He participated in significant battles, including Chancellorsville and Gettysburg. Around the time of Gettysburg, Sladen joined the staff of General Oliver Otis Howard, initiating a professional relationship that would last for decades. He was awarded the Medal of Honor, with a citation for bravery at the Battle of Resaca in 1864, where he voluntarily joined the fight and inspired his comrades.

 After the war Sladen continued his service in the army, transitioning into the post-war era with an important assignments as aide-de-camp to General Oliver Otis Howard (who had lost his right arm at the Battle of Fair Oaks in 1862) and in the Freedmen's Bureau, the organization charged with supervising nearly 4 million liberated enslaved people.

As an extension of his work with General Howard with the Freedman's Bureau, he participated in the the creation of Howard University, serving as the school's secretary and at the same time earning a Medical Degreed from Howard University in 1871.

Sladen's most notable contribution during the Frontier Indian Wars was his involvement in the 1872 peace negotiations with the Chiricahua Apache leader Cochise. As General Howard's aide-de-camp, Sladen journeyed through New Mexico and Arizona, a pivotal expedition he detailed in his account "Making Peace With Cochise." This successful mission led to a treaty with Cochise, marking a significant achievement in the fraught relationships between Native Americans and the United States government during this era.

After the successful mission with Cochise, Sladen's military career continued in the West. In 1874, when Howard was assigned as commander of the Army's Department of the Columbia, Sladen joined him in Portland, Oregon. Here, Sladen's duties were diverse, ranging from aide-de-camp to assistant adjutant and acting judge advocate. This period was marked by significant engagements, including the Nez Perce War of 1877 and the Bannock War of 1878, where Sladen's expertise and experience were instrumental. In later years Sladen faced personal challenges, including severe injuries leading to the loss of his leg.

Sladen's service in the West was not without personal challenges. In 1875, a riding accident at Fort Walla Walla, Washington, resulted in a severe leg injury, leading to amputation. Despite this setback, Sladen continued his service with determination. In 1876, he sustained another injury to the same leg, further complicating his physical condition. Nevertheless, Sladen's resilience and commitment to his duties remained steadfast.

In 1881, Sladen's path once again intersected with Howard's when the latter was appointed Superintendent of the United States Military Academy. Sladen served on his staff as the academy's adjutant. The following year, Howard University awarded him an honorary Master of Arts degree in 1882.

Sladen's military career in the West culminated with his assignment to Fort Omaha, Nebraska, in 1882, where he continued to serve under Howard's command in the Department of the Platte. In 1885, he was transferred to the 14th Infantry at Vancouver Barracks, Washington.    

Post-military, Sladen settled in Portland, Oregon, embarking on a successful career in insurance and banking, and serving as a clerk of the U.S. Circuit Court. He remained active in civic and professional organizations, contributing significantly to his community until his death in 1911.